Dolly the sheep creator says live mammoth possible

DOLLY the sheep creator Professor Sir Ian Wilmut says woolly mammoths could be brought back from extinction using stem cells.

Sir Ian, Emeritus professor at the MRC Centre for Regenerative Medicine at Edinburgh University, wrote in a scientific paper about his thoughts on how the extinct beasts could be brought back to life.

The scientist said the same methods used to create Dolly in 1996 would not work for recreating a mammoth.

However, he said there were other ways in which it would be “biologically interesting to work with viable mammoth cells if they can be found”.

“In order for a Dolly-like clone to be born it is necessary to have females of a closely related species to provide unfertilised eggs and, if cloned embryos are produced, to carry the pregnancies,” Sir Ian wrote.

“Cloning depends on having two cells. One is an egg recovered from an animal around the time when usually she would be mated.”

He said there would need to be several hundred to 1000 eggs to allow an opportunity to optimise the cloning techniques. One suggestion is to use eggs from elephants but, as Sir Ian pointed out, it is not appropriate to try and obtain 500 eggs from a mammal that is becoming extinct.

Instead, he says it could be possible to obtain a few mature elephant eggs and transplant them into mice, which could yield a considerable amount of eggs.

The chances of cells found in mammoths in the frozen Siberian landscape being viable would increase if bones could be recovered from the lowest possible temperature.

Sir Ian said cells will degenerate rapidly as the temperature lowers to the point that snow and ice melts, so even those at the coldest temperature could become useless as they thaw.

He said scientists would need to introduce the mammoth nucleus into an egg immediately, by injecting the contents of the damaged cell into the egg. If this results in embryo development, then it would need to be transferred to surrogate mothers to develop through pregnancy. Embryo transfer is carried out in fewer than a dozen species and the elephant is not one of them.

He said: “There is no guarantee that these techniques are even biologically possible. There may be unknown differences between species that would prevent the procedures that we developed in sheep being successful, despite the uncertainties of this technique.”